1. Field of the Invention
This invention relates to a magnetic disk cartridge comprising a disk case, and a magnetic disk rotatably supported by liner members in the disk case.
2. Description of the Prior Art
In general, magnetic disk cartridges are constituted by securing a pair of disk-like liner members formed of a nonwoven fabric respectively to inner surfaces of upper and lower case halves of a disk case, and supporting a magnetic disk rotatably with respect to the disk case by the liner members. The liner members rotatably support the magnetic disk and clean the magnetic disk while the magnetic disk is being rotated. Dust debris and the like which cling to the surface of the magnetic disk are caught among fibers of the nonwoven fabric.
In the aforesaid conventional magnetic disk cartridge, the nonwoven fabric used as the liner members has the effect of collecting dust, debris or the like present on the surfaces of the magnetic disk. However, part of the fibers constituting the nonwoven fabric separate from the nonwoven fabric, for example, when the magnetic disk cartridge receives an impact, and cling as dust to the surface of the magnetic disk. Thus the nonwoven fabric itself constitutes a source of dust clinging to the magnetic disk. Also, the nonwoven fabric is mainly formed of a material such as rayon, polyester or polypropylene which has a comparatively large coefficient of friction .mu.. Therefore, the frictional resistance is high and it is not always possible to increase the rotation speed of the magnetic disk for the purpose of, for example, improving the data transfer rate. The conventional magnetic disk cartridge also has the drawback that, since the nonwoven fabric and the magnetic disk exhibit a high electrical resistance, the magnetic disk is electrostatically charged and dust, debris or the like readily cling thereto when the magnetic disk is rotated.